Sine of theta is the ratio of the lengths of the Opposite side over the Hypotenuse (SOH). Cosine of theta is Adjacent over Hypotenuse (CAH). Tangent of theta is Opposite over Adjacent (TOA).
It's not. It's just one of those things that people groan about because when you first learn it the concept is confusing. After about 15 minutes of instruction on a unit circle, it's not a big deal at all.
So the picture is wrong then, the marked angle is top right (and the right angle, of course), the other angle is not marked, so adjacent and opposite are swapped.
The one with the Jedi? Yes, was wondering about that too. If you get through the trouble creating something like that you should really try to make it right.